I dunno man, it's been ages since I've read him up. It very well could simply be an aversion/inclination thing, though if my memory serves me correctly in some of the experiments the plants would shy away from people who had previously harmed them - specifically a case where a man burned a branch off of a bush and then two days later when he walked into the room with the bush completely unarmed the plant tried to get away from him as best it could.
On an unrelated subject, the best reasoning I've heard for being a vegetarian comes from a co-worker of mine who says that the reason he's gone veg is because he hates plants and wants to murder and devour as many of them as he can.
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chumbucketeer fills cups like double-Ds.
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